Three-phase power supply phase loss detection circuit and motor controller of BLDC motor
The technical field is as follows:
the utility model relates to a three-phase power supply open-phase detection circuit and a motor controller of a BLDC motor.
Background art:
in the industry, regarding a direct current three-phase motor, only the three-phase end open-phase protection of a motor part is usually considered, and the power end is not monitored by neglecting the three-phase input of a power supply part, so that when the power supply is in an open phase, a product cannot detect abnormality and continues to operate, and finally the product is damaged, and the reliability of the product is poor.
The utility model content is as follows:
the utility model aims to provide a three-phase power supply phase-lack detection circuit and a motor controller of a BLDC motor thereof, which can solve the technical problem that in the prior art, when a power supply phase-lack occurs, a product cannot detect abnormality and continues to operate, and finally the product is damaged.
The purpose of the utility model is realized by the following technical scheme.
The utility model aims to provide a three-phase power supply open-phase detection circuit, which is characterized in that: including 3 rectifier circuit, step-down circuit, comparison circuit of way, three-phase input power U, V, W is connected respectively to 3 rectifier circuit's input, and 3 rectifier circuit's output links together as step-down circuit's input, and step-down circuit's output is connected to comparison circuit's input, and comparison circuit's output is as three-phase power supply phase failure signal output.
The 1-path rectifying circuit consists of a diode and a current-limiting resistor.
The voltage reduction circuit is formed by connecting a resistor R4 and a resistor R5 in series, wherein one end of the resistor R4 and the resistor R5 are connected in series and then grounded, and the other end of the resistor R4 and the other end of the resistor R5 are connected with the output end of the rectifying circuit.
The comparison circuit comprises a comparator IC1, a voltage division resistor R6 and a voltage division resistor R7; after the resistor R6 and the resistor R7 are connected in series, one end of the resistor R6 is connected with a power supply VCC, the other end of the resistor R7 is grounded GND, the middle point of the resistor R6 and the resistor R7 is a comparison reference voltage and serves as one input end of the comparator IC1, and the other comparison input end of the comparator IC1 is led out between the resistor R4 and the resistor R5.
A motor controller of a BLDC motor, characterized in that: including three-phase rectifier circuit, inverter circuit and microprocessor MCU, three-phase input power U, V, W is connected to three-phase rectifier circuit's input, three-phase rectifier circuit's output is connected to DC-DC conversion power supply circuit input, DC-DC conversion power supply circuit's output provides different supply voltage and supplies power for inverter circuit and microprocessor MCU, microprocessor MCU is according to the work of the parameter output control signal control inverter circuit of motor operation process, the stator coil winding of BLDC motor is connected to inverter circuit's output, its characterized in that: the three-phase power supply open-phase detection circuit is characterized in that the three-phase power supply open-phase detection circuit is the three-phase power supply open-phase detection circuit, the output end of the comparison circuit is connected with the input end of the microprocessor MCU, the microprocessor MCU judges whether open-phase exists or not according to the output signal of the comparison circuit, and if the open-phase exists, the microprocessor MCU controls the inverter circuit to stop the machine.
Compared with the prior art, the utility model has the following effects:
1) a three-phase power supply phase loss detection circuit is characterized in that: including 3 rectifier circuit ways, the step-down circuit, comparison circuit, three-phase input power U, V, W is connected respectively to 3 rectifier circuit's input, 3 rectifier circuit's output links together as step-down circuit's input, step-down circuit's output is connected to comparison circuit's input, comparison circuit's output lacks looks signal output as three-phase power, when detecting that input power appears lacking looks, can make the shutdown operation at once, protection components and parts, improve circuit's stability and reliability, circuit structure is simple.
2) Other advantages of the present invention are described in detail in the examples section.
Description of the drawings:
FIG. 1 is a schematic diagram of a first embodiment of the present invention;
FIG. 2 is a schematic diagram of another embodiment of the present invention;
fig. 3 is a waveform diagram of a three-phase input power U, V, W without phase loss according to an embodiment of the present invention;
fig. 4 is a waveform diagram of a three-phase input power U, V, W under a phase-loss condition according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a second embodiment of the present invention.
The specific implementation mode is as follows:
the present invention will be described in further detail below with reference to specific embodiments and with reference to the accompanying drawings.
The first embodiment is as follows:
as shown in fig. 1 to 4, the present embodiment provides a three-phase power supply phase-loss detection circuit, which is characterized in that: including 3 rectifier circuit ways, the step-down circuit, comparison circuit, three-phase input power U, V, W is connected respectively to 3 rectifier circuit's input, 3 rectifier circuit's output links together as step-down circuit's input, step-down circuit's output is connected to comparison circuit's input, comparison circuit's output lacks looks signal output as three-phase power, when detecting that input power appears lacking looks, can make the shutdown operation at once, protection components and parts, improve circuit's stability and reliability, circuit structure is simple.
When the three-phase input power U, V, W is in a condition of no phase loss, the waveform condition of the port at the output terminal of the comparator is distributed on the limit line, as shown in fig. 3.
When the three-phase input power U, V, W is in the phase-loss condition, the waveform condition of the port at the comparator output is distributed between the limit lines, as shown in fig. 4.
The 1-path rectifying circuit consists of a diode and a current-limiting resistor; the first circuit of the rectifying circuit consists of a diode D1 and a current-limiting resistor R1; the second circuit of the rectifying circuit consists of a diode D2 and a current-limiting resistor R2; the third circuit of the rectifying circuit consists of a diode D3 and a current-limiting resistor R3.
The voltage reduction circuit is formed by connecting a resistor R4 and a resistor R5 in series, wherein one end of the resistor R4 and the resistor R5 are connected with the ground after being connected in series, and the other end of the resistor R4 and the resistor R5 are connected with the output end of the rectification circuit.
The comparison circuit comprises a comparator IC1, a voltage-dividing resistor R6 and a voltage-dividing resistor R7; after the resistor R6 and the resistor R7 are connected in series, one end of the resistor R6 is connected with a power supply VCC, the other end of the resistor R7 is grounded GND, the middle point of the resistor R6 and the resistor R7 is a comparison reference voltage and serves as one input end of the comparator IC1, and the other comparison input end of the comparator IC1 is led out between the resistor R4 and the resistor R5.
Example two:
as shown in fig. 5, a motor controller of a BLDC motor is characterized in that: including three-phase rectifier circuit, inverter circuit and microprocessor MCU, three-phase input power U, V, W is connected to three-phase rectifier circuit's input, three-phase rectifier circuit's output is connected to DC-DC conversion power supply circuit input, DC-DC conversion power supply circuit's output provides different supply voltage and supplies power for inverter circuit and microprocessor MCU, microprocessor MCU is according to the work of the parameter output control signal control inverter circuit of motor operation process, the stator coil winding of BLDC motor is connected to inverter circuit's output, its characterized in that: the three-phase power supply open-phase detection circuit is the three-phase power supply open-phase detection circuit in the first embodiment, the output end of the comparison circuit is connected with the input end of the microprocessor MCU, the microprocessor MCU judges whether open-phase exists according to the output signal of the comparison circuit, if the open-phase exists, the microprocessor MCU controls the inverter circuit to stop operating, components and parts are protected, the stability and reliability of the circuit are improved, and the circuit structure is simple.
The above embodiments are only preferred embodiments of the present invention, but the present invention is not limited thereto, and any other changes, modifications, substitutions, combinations, simplifications, which are made without departing from the spirit and principle of the present invention, are all equivalent replacements within the protection scope of the present invention.